Currently most commercial buildings and some apartment complexes are constructed making use of steel supported concrete floors and roofs. Traditional methods employ steel joists, usually being placed parallel to one another, being secured at each of their ends to structural building members such as steel or concrete beams or girders. Each joist end rests on these members, the beams generally running perpendicular to the placement of the joists. The steel joist themselves are usually of the open-web design, each one consisting of a zigzag shaped rod connecting a joist top chord and a bottom chord which run a spaced distance apart and parallel to one another. Both the top and bottom chords are comprised of opposed angle iron members affixed together by means of the apices of the connecting rod. The bearing end of each joist is further comprised of a pair of flange connected seat angles extending laterally from each opposed angle iron so as to form a pair of U shaped channels at each joist bearing end. Corrugated metal decking is then placed on top of the joists, and finally concrete is poured over the corrugated decking and the joist ends and top surface of the beams or girders.
An important step in concrete steel structures is to insure a fully composite structure is created between the concrete, joist ends, and top surface of the beams. Benefits of composite structure include stronger, stiffer concrete slabs; lower building costs due to less weight of the beams and joists; decreased sound and vibrations transmission; floors more resistant to bounce and wind deflection. To accomplish this shear studs are affixed adjacent the joist ends on the top surface of the beams and metal pans are secured between the joist ends, the edge of the corrugated deck, and the top surface of the beam. Concrete is now poured over the combination of the composite pan, shear studs, joist ends, beam top surface, and the top surface of the corrugated decking. The composite pan forms the end connection for this composite beam-joist system, and causes the concrete to haunch down onto the beam surface, making it composite with the concrete slab.
The present invention discloses novel and useful composite pan structures, which will be fully described and illustrated below.
It is therefore a primary object of the present invention to provide a superior composite pan, composite beam-joist construction.
It is a further object of the invention to provide a rectangular and therefore structurally more efficient shape of the concrete slab on the beam.
An additional object of the invention is to provide a simplified and economical method of manufacture for a composite pan.
Yet another object of the invention is to provide a composite pan for both conventional open web joists as well as composite open web joists.
Still another object of the invention is to provide a composite pan for operator positioning either above or below the joist top chords.
An additional object of the invention is to provide a composite pan that can be formed on a standard break machine.